Electrochromism refers to a phenomenon of reversible color change of a material's appearance due to a reversible change of light transmission or reflection resulted by oxidation or reduction under an action of external electric field. At present, applications of electrochromic materials mainly include electrochromic display devices, smart windows and glare-less rearview mirrors of automobiles.
Conventional electrochromic display devices (ECDs) are small in size and can not meet the demand for large size display. And the display modes of the conventional electrochromic display devices are the same as conventional displays, which can only display images or white screen, and the display functions are few only.